/* Layout: a field-survey sheet. Soil cross-section hero, then a single reading column with a sticky quote card on wide screens. */
:root {
  --paper: #eef1ec;      /* survey-sheet grey-green */
  --sheet: #f8faf6;      /* raised surfaces */
  --ink: #1d2a24;        /* pine ink */
  --muted: #56645c;
  --rule: #c9d1c8;
  --clay: #a8452a;       /* Piedmont red clay, the one accent */
  --clay-ink: #ffffff;
  --soil-1: #b9805f;
  --soil-2: #9a5a3c;
  --soil-3: #7b4430;
  --steel: #4b5a63;
  --ok: #2f6b45;
  --warn: #8a5a00;
  --f-display: "Barlow Condensed", "Arial Narrow", "Roboto Condensed", sans-serif;
  --f-body: "IBM Plex Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --f-mono: "IBM Plex Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;
  --step--1: 0.875rem;
  --step-0: 1.0625rem;
  --step-1: 1.3rem;
  --step-2: 1.7rem;
  --step-3: 2.3rem;
  --step-4: clamp(2.4rem, 6vw, 3.6rem);
  --radius: 6px;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #141b18; --sheet: #1b2420; --ink: #e4ebe6; --muted: #9fb0a6; --rule: #2e3b35;
    --clay: #e0795a; --clay-ink: #1a0f0a; --soil-1: #6e4a37; --soil-2: #5a3a2a; --soil-3: #452c20;
    --steel: #8fa1ab; --ok: #7cc797; --warn: #e2b55c; color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --paper: #141b18; --sheet: #1b2420; --ink: #e4ebe6; --muted: #9fb0a6; --rule: #2e3b35;
  --clay: #e0795a; --clay-ink: #1a0f0a; --soil-1: #6e4a37; --soil-2: #5a3a2a; --soil-3: #452c20;
  --steel: #8fa1ab; --ok: #7cc797; --warn: #e2b55c; color-scheme: dark;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--paper); color: var(--ink);
  font-family: var(--f-body); font-size: var(--step-0); line-height: 1.6;
}
a { color: var(--clay); text-underline-offset: 3px; }
a:focus-visible, button:focus-visible, input:focus-visible, select:focus-visible, textarea:focus-visible, summary:focus-visible {
  outline: 3px solid var(--clay); outline-offset: 2px;
}
h1, h2, h3 { font-family: var(--f-display); font-weight: 700; line-height: 1.05; text-wrap: balance; margin: 0; letter-spacing: 0.005em; }
h1 { font-size: var(--step-4); }
h2 { font-size: var(--step-3); }
h3 { font-size: var(--step-1); font-family: var(--f-body); font-weight: 600; line-height: 1.3; }
p { margin: 0; }
.wrap { max-width: 1120px; margin: 0 auto; padding-inline: 20px; }
.label { font-family: var(--f-mono); font-size: 0.75rem; letter-spacing: 0.12em; text-transform: uppercase; color: var(--muted); }

/* Header */
.site-head { border-bottom: 1px solid var(--rule); background: var(--paper); }
.site-head .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; padding-block: 14px; flex-wrap: wrap; }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--ink); }
.brand svg { width: 30px; height: 30px; flex: none; }
.brand b { font-family: var(--f-display); font-size: 1.45rem; letter-spacing: 0.02em; text-transform: uppercase; }
.site-nav { display: flex; gap: 18px; flex-wrap: wrap; font-size: var(--step--1); }
.site-nav a { color: var(--ink); text-decoration: none; }
.site-nav a:hover { color: var(--clay); }

/* Hero */
.hero { padding-block: 40px 0; }
.hero-grid { display: grid; grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr); gap: 40px; align-items: start; }
.hero-copy { display: grid; gap: 18px; min-width: 0; }
.hero-copy .lede { font-size: var(--step-1); line-height: 1.45; max-width: 34ch; }
.hero-points { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; }
.hero-points li { display: flex; gap: 10px; align-items: baseline; }
.hero-points li::before { content: ""; flex: none; width: 10px; height: 10px; background: var(--clay); border-radius: 2px; transform: translateY(1px); }
.section-svg { width: 100%; height: auto; display: block; margin-top: 8px; }

/* Quote card */
.quote-card { background: var(--sheet); border: 1px solid var(--rule); border-radius: var(--radius); padding: 22px; display: grid; gap: 14px; box-shadow: 0 1px 0 var(--rule), 0 12px 30px -18px rgba(0,0,0,0.25); min-width: 0; }
.quote-card h2 { font-size: var(--step-2); }
.quote-card .sub { color: var(--muted); font-size: var(--step--1); }
form { display: grid; gap: 12px; }
.row2 { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.field { display: grid; gap: 4px; min-width: 0; }
.field label, fieldset legend { font-size: var(--step--1); font-weight: 600; }
input[type=text], input[type=tel], input[type=email], select, textarea {
  width: 100%; font: inherit; font-size: 1rem; color: var(--ink); background: var(--paper);
  border: 1px solid var(--rule); border-radius: 4px; padding: 10px 12px;
}
textarea { min-height: 72px; resize: vertical; }
fieldset { border: 0; padding: 0; margin: 0; display: grid; gap: 6px; }
.chips { display: flex; flex-wrap: wrap; gap: 6px; }
.chips label { display: inline-flex; align-items: center; gap: 6px; border: 1px solid var(--rule); border-radius: 999px; padding: 6px 12px; font-size: var(--step--1); font-weight: 500; cursor: pointer; background: var(--paper); }
.chips input { accent-color: var(--clay); margin: 0; }
.chips label:has(input:checked) { border-color: var(--clay); color: var(--clay); }
.consent { display: flex; gap: 8px; align-items: flex-start; font-size: var(--step--1); color: var(--muted); }
.consent input { margin-top: 4px; accent-color: var(--clay); }
.hp { position: absolute; left: -9999px; width: 1px; height: 1px; overflow: hidden; }
.btn { font: inherit; font-weight: 600; font-size: 1.05rem; border: 0; border-radius: 4px; padding: 13px 18px; background: var(--clay); color: var(--clay-ink); cursor: pointer; }
.btn:hover { filter: brightness(1.06); }
.btn[disabled] { opacity: 0.6; cursor: progress; }
.form-msg { font-size: var(--step--1); }
.form-msg.err { color: var(--clay); }
.done { display: grid; gap: 10px; }
.done h2 { color: var(--ok); }
.fineprint { font-size: 0.8rem; color: var(--muted); }

/* Body sections */
main section { padding-block: 56px; border-top: 1px solid var(--rule); }
.hero + section { margin-top: 48px; }
.sec-head { display: grid; gap: 8px; margin-bottom: 26px; max-width: 62ch; }
.prose { max-width: 66ch; display: grid; gap: 14px; }
.prose ul, .prose ol { margin: 0; padding-left: 1.2em; display: grid; gap: 6px; }

.signs { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 22px; }
.sign { display: grid; gap: 8px; align-content: start; }
.sign svg { width: 56px; height: 56px; }
.sign p { color: var(--muted); font-size: 0.97rem; }

.options { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 0; border: 1px solid var(--rule); border-radius: var(--radius); overflow: hidden; background: var(--sheet); }
.option { padding: 20px; display: grid; gap: 8px; align-content: start; border-right: 1px solid var(--rule); }
.option:last-child { border-right: 0; }
.option .tag { font-family: var(--f-mono); font-size: 0.72rem; letter-spacing: 0.1em; text-transform: uppercase; }
.option .tag.good { color: var(--ok); }
.option .tag.mid { color: var(--warn); }
.option p { font-size: 0.97rem; color: var(--muted); }

.rules { display: grid; gap: 0; max-width: 820px; }
.rule { display: grid; grid-template-columns: 120px minmax(0, 1fr); gap: 18px; padding-block: 16px; border-bottom: 1px dashed var(--rule); }
.rule:first-child { border-top: 1px dashed var(--rule); }
.rule .k { font-family: var(--f-mono); font-size: 0.8rem; color: var(--clay); padding-top: 3px; }

.who { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 26px; }
.who > div { display: grid; gap: 8px; align-content: start; }
.who p { color: var(--muted); font-size: 0.97rem; }

details { border-bottom: 1px solid var(--rule); padding-block: 14px; max-width: 820px; }
details:first-of-type { border-top: 1px solid var(--rule); }
summary { cursor: pointer; font-weight: 600; list-style: none; display: flex; justify-content: space-between; gap: 12px; }
summary::after { content: "+"; font-family: var(--f-mono); color: var(--clay); }
details[open] summary::after { content: "–"; }
details p { margin-top: 10px; color: var(--muted); max-width: 66ch; }

.towns { display: flex; flex-wrap: wrap; gap: 8px; list-style: none; padding: 0; margin: 0; }
.towns a { color: var(--ink); text-decoration: none; }
.towns a:hover { color: var(--clay); }
.towns li { font-family: var(--f-mono); font-size: 0.85rem; border: 1px solid var(--rule); border-radius: 999px; padding: 4px 12px; background: var(--sheet); }

.cta-band { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 18px; background: var(--ink); color: var(--paper); padding: 26px; border-radius: var(--radius); }
.cta-band h2 { font-size: var(--step-2); color: var(--paper); }
.cta-band .btn { text-decoration: none; display: inline-block; }

.site-foot { border-top: 1px solid var(--rule); padding-block: 30px 40px; font-size: var(--step--1); color: var(--muted); }
.site-foot .wrap { display: grid; gap: 10px; }
.site-foot nav { display: flex; gap: 16px; flex-wrap: wrap; }
.site-foot a { color: var(--muted); }

/* Article pages */
.article { padding-block: 40px 20px; }
.article .prose h2 { font-size: var(--step-2); margin-top: 18px; }
.article .prose h1 { margin-bottom: 4px; }
.table-scroll { overflow-x: auto; }
table { border-collapse: collapse; width: 100%; font-size: 0.95rem; font-variant-numeric: tabular-nums; }
th, td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--rule); vertical-align: top; }
th { font-family: var(--f-mono); font-size: 0.75rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); font-weight: 500; }

@media (max-width: 860px) {
  .hero-grid { grid-template-columns: minmax(0, 1fr); }
  .option { border-right: 0; border-bottom: 1px solid var(--rule); }
  .option:last-child { border-bottom: 0; }
}
@media (max-width: 480px) {
  .row2 { grid-template-columns: 1fr; }
  .rule { grid-template-columns: 1fr; gap: 4px; }
  .wrap { padding-inline: 16px; }
}
@media (prefers-reduced-motion: no-preference) {
  .tank-probe { animation: probe 3.2s ease-in-out infinite; }
  @keyframes probe { 0%,100% { transform: translateX(0); } 50% { transform: translateX(26px); } }
}